Non-transparent art paper which prevents ink seepage

Abstract

A non-transparent paper is described for non-transparent art or graphic design sketches, which prevents seepage of the inks, it accepts any type of gel, water-based, solvent-based, oil-based or mixed inks and solid materials for sketching and drawing, as well as fixatives for the solid materials. This paper consists of a lamination of at least two sheets of uncoated bond paper, inserting at least one intermediate layer of pigmented opacifying emulsion between both sheets, applied between the layers of paper to prevent transparency and the seepage of inks from one face of the lamination to the other. This layer of emulsion contains at least one opacifying pigment, at least one adhesive, agents to control viscosity and surface tension and other components. The outside layers of paper have a drying capacity which fixes the materials used for the sketching and prevent outlines made on one face passing to the adjacent sheets of paper, and also has a texture suitable for receiving any dry material for drawing or sketching.

We claim: 
     
         1 . A sketch paper for art and design applications comprising:
 (a) at least two base sheets of bond paper, wherein the sheets of bond paper are of the same type and same weight; and   (b) at least one intermediate layer inserted between and coupled to the two base sheets, wherein the intermediate layer comprises an emulsion;   such that the sketch paper is at substantially opaque and both sides of the paper are suitable for the application of dry drawing and non-dry art materials.   
     
     
         2 . The sketch paper of  claim 1 , wherein the emulsion comprises:
 (a) at least one chemical opacifier compound;   (b) at least one adhesive;   (c) at least one styrene copolymer emulsion; and   (d) at least one viscosity and surface tension control agent.   
     
     
         3 . The sketch paper of  claim 2 , wherein at least one chemical opacifier compound is selected from the group of carbon black, rutile titanium dioxide, anatase titanium dioxide, calcium carbonate, kaolin with laminar structure, calcined kaolin, white polymers, organic pigments, and inorganic pigments. 
     
     
         4 . The sketch paper of  claim 3 , wherein at least one chemical opacifier compound has an average particle size of between 0.5 microns and 2 microns. 
     
     
         5 . The sketch paper of  claim 2 , wherein at least one styrene copolymer emulsion is selected from the group of styrene-butadiene copolymers, styrene-acrylic emulsion copolymers, styrene-acetylated starch copolymers, styrene-oxidized starch copolymers, and styrene-low viscosity highly hydrolyzed polyvinyl alcohols copolymers. 
     
     
         6 . The sketch paper of  claim 2 , wherein at least one viscosity and surface tension control agent is an acrylic polymer. 
     
     
         7 . The sketch paper of  claim 2 , wherein at least one viscosity and surface tension control agent is a non-ionic surfactant. 
     
     
         8 . The sketch paper of  claim 7 , wherein at least one viscosity and surface tension control agent is selected from consisting of surfynole ct-131, surfynole ct-171, Solfix 855, and triton X-100. 
     
     
         9 . The sketch paper of  claim 2 , wherein the inside of each base sheet is coated with a mixture comprising 50% carboxylated polyvinyl alcohol (99% hydrolysis), 0.5% Triton X-100, 45% insolubilizing resin, and 4.5% Acrylic styrene. 
     
     
         10 . The sketch paper of  claim 9  wherein the insolubilizing resin comprises cationic polymers of polyamine-epichlorhydrine. 
     
     
         11 . The sketch paper of  claim 2 , further comprising at least one synthetic and/or natural resin on at least one of the inside and the outside of each base sheet. 
     
     
         12 . The sketch paper of  claim 11 , wherein at least one resin is selected from the group consisting of polyolefins, polyethylene, polypropylene, styrene acrylic resins, polyester resins, other polymers, waxes and silicones. 
     
     
         13 . The sketch paper of  claim 2 , further comprising at least one additional intermediate layer inserted between the two base sheets, wherein at least one such additional intermediate layer comprises one or more additional emulsions. 
     
     
         14 . The sketch paper of  claim 2 , wherein the two base sheets may have different finishes on the outside of each base sheet. 
     
     
         15 . The sketch paper of  claim 14 , wherein at least one of the base sheets may be covered with at least one finishing material selected from the group of kaolins and adhesives. 
     
     
         16 . The sketch paper of  claim 2 , wherein at least one of the base sheets is impregnated with one or more cationic wet strength additives. 
     
     
         17 . The sketch paper of  claim 16 , wherein at least one of the base sheets is further impregnated with one or more carboxylated polyvinyl alcohols. 
     
     
         18 . The sketch paper of  claim 2 , wherein the opacity of the sketch paper is between 88% and 99.5% TAPPI T-452. 
     
     
         19 . The sketch paper of  claim 2  wherein the TAPPI T-425 brightness of the sketch paper is between 88 to 90%. 
     
     
         20 . The sketch paper of  claim 2 , wherein the finish of the sketch paper has a Gurley Hill porosity of between 20 and 10 sec/100 ml. 
     
     
         21 . The sketch paper of  claim 2 , wherein the weight of the base papers is between 68 and 100 g/m 2 . 
     
     
         22 . The sketch paper of  claim 2 , wherein the composition by percent weight of said emulsion is 5% kaolin with laminar structure, 5% calcined kaolin, 0.5% Surfynol ct 171, 0.5% insolubilizer, 58% acrylic emulsions, 30% styrene acrylic polymers, and 1% carbon black. 
     
     
         23 . The sketch paper of  claim 2 , wherein the composition by percent weight of said emulsion is 10% calcined kaolin, 0.5% Surfynol ct 171, 0.5% insolubilizer, 59% acrylic emulsions, 30% styrene acrylic polymers, and 1% carbon black. 
     
     
         24 . The sketch paper of  claim 2 , wherein the composition by percent weight of said emulsion is 5% calcined kaolin, 5% anatase titanium dioxide, 0.5% Surfynol ct 171, 0.5% insolubilizer, 59% acrylic emulsions, 29% styrene acrylic polymers, and 1% carbon black. 
     
     
         25 . The sketch paper of  claim 2 , wherein the composition by percent weight of said emulsion is 5% calcined kaolin, 5% anatase titanium dioxide, 0.5% Surfynol ct 171, 0.5% insolubilizer, 58% acrylic emulsions, 30% styrene acrylic polymers, and 1% carbon black. 
     
     
         26 . The sketch paper of  claim 2 , further comprising at least one additional intermediate layer of paper placed between the two base sheets, wherein this intermediate paper layer may be coated on one or both sides by resins, and wherein at least one resin is selected from the group consisting of polyolefins, polyethylene, polypropylene, styrene acrylic resins, polyester resins, or other polymers, waxes, and silicones.